the numerous, moderate size (few large), shallow, scutal puncta- 

 tions that are uniformly and vridely distributed over most of the 

 scutal surface, is a combination of characters easily separating 

 males from those of all other species. 



Variation in each of these characters are as follows; (l) 

 In specimens that have fed, the subanal shields are always 

 situated well exterior of the axis of the adanal shields; they 

 are usually borne on a slightly rounded, elevated protrusion 

 of the ventral integument, and losually extend posterior beyond 

 the body margin. However, in unfed specimens, where the subu. 

 anal shields are still closely appressed to the ventral integu- 

 ment, these shields may appear to be in line with the central 

 axis of the adanal shields. Close observation reveals that the 

 base of the subanal shields is in an exterior position but that 

 the unique tilting of the subanal shields in a medially-directed 

 position gives the first impression that they are situated direct- 

 ly posterior of the adanal shields. In fed males, the subanal 

 shields are visually vertical and parallel. (2) The lateral grooves 

 are iisually well delineated and extend from the festoons in a 

 progressively more shallow line almost to the eyes. In some spec- 

 imens, they are more or less obscured, at the level of the scutal 

 midlength and anteriorly, by scutal punctations; questionable spec- 

 imens should be tilted towards the sovirce of the light. In other 

 individuals, the anterior extension of the lateral grooves con- 

 sists chiefly of a distinct row of more or less contiguous puncta- 

 tions; such specimens may be confused with H. dromedarii , and, if 

 the subanal shields are still closely appressed to the ventral 

 integument, possibly even with H. excavatum . (3) Punctations are 

 usually very slightly larger, deeper, and more dense posteriorly 

 than elsewhere on the scutum. Punctations over the scutum are 

 typically dense but not contiguous, regular, medium-size with a 

 few scattered larger, deeper ones among them, and fairly shallow. 

 The nvunber and placement of these punctations is subject to con- 

 siderable variation; in some specimens the central scutal area may 

 be almost devoid of obvious punctations; this is especially true 

 in engorged individuals. 



Other characters are as follows: The area just anterior of 

 the festoons is almost always slightly depressed and contains a 

 long, narrow posteromedian groove, and a pair of shorter, wider. 



- 458- 



